There's mucus or a little blood in my puppy's poop. Should I worry?

By Dr. Steve Pelton, DVM

The short answer

A little mucus or a small streak of red on a soft stool usually means the lower gut is irritated. In a bright, playful puppy, that's a call to your vet today, not an emergency. A lot of blood, black tarry poop, or any blood in a puppy who's tired or vomiting means go now.

Why it happens

The last stretch of the gut makes mucus when it's irritated, and a tiny vessel near the end can leave a streak of red. Black, tarry poop is different, because that's blood from higher up.

Which door?

CALL TODAYIn a bright puppy.
GO NOWThere's a lot of blood, it's black and tarry, or he's tired.

When to call

Tick what fits and see which door you're at.

CALL TODAYMucus or a small streak of blood, and he's acting normal
GO NOWA lot of blood, or black, tarry poop
GO NOWAny blood in a puppy who's tired or vomiting

Your door: WATCHWATCH

Nothing ticked and he's bright, playful, eating and drinking? Keep an eye on him, jot down what you see, and call in the daytime if it doesn't settle.

Under 16 weeks, a toy breed, or not done with his shots? Move everything one door closer to GO NOW.

GO NOW means: Head to your vet, if they're open and can see him right away, or to the nearest emergency clinic. Call on the way so they're ready for you.

Not sure which door you're at? That's a call. Call your vet.

Worried right now? Check the Three Doors list, from most urgent down, and stop at the first door that fits.

Is this an emergency?

General education, not veterinary advice. Your vet's plan for your puppy comes first.